Most prior art surface cleaning vehicles, such as factory floor sweepers, sidewalk sweepers, and street sweepers, use a debris pick-up head of one sort or another to engage a surface to be cleaned as the surface cleaning vehicle travels along. In order to preclude the escape of dust and other fine particulate matter from the debris pick-up head during use, air is suctioned from the debris pick-up head by the main fan of the vehicle. The debris pick-up head engages the ground in a semi-sealed relation in order to preclude the escape of dust and other fine particulate matter from between the debris pick-up head and the surface to be cleaned.
One very significant problem with such a system is that as the debris pick-up head traverses over the surface to be cleaned, it often encounters significant unevenness in the surface to be cleaned, such a potholes, speed bumps, and the like. In this case, at least a portion of the bottom edge of the debris pick-up head becomes temporarily separated from the surface to be cleaned. Accordingly, the dust and other fine particulate matter are thereby potentially allowed to escape from between the debris pick-up head and the surface to be cleaned, due to the loss of reduced air pressure within the pick-up head.
One solution to this problem is to increase the speed of the main fan, thereby increasing the suction of air from the debris pick-up head. It is well known that this solution does not work effectively because the main fan cannot be sped up quickly enough to apply significantly increased suction to the debris pick-up head while the separation exists between the debris pick-up head and the surface to be cleaned as the vehicle continues to travel.
In order to work effectively and solve the problem of debris escaping between the debris pick-up head and the surface to be cleaned, the increased suction of air from the debris pick-up head must be available virtually immediately once there is a separation between the debris pick-up head and the surface to be cleaned.
It is an object of the present invention to provide a dustless debris pick-up head system.
It is an object of the present invention to provide a debris pick-up head system wherein increased suction of air from the debris pick-up head is available virtually immediately once there is a separation between the debris pick-up head and the surface to be cleaned.